Holmes HAP8650B-U True HEPA Allergen Remover operates quietly to help remove up to 99.97% of airborne allergens such as pollen, dust, mold, pet dander and smoke to provide relief from irritants in the air. ARM & HAMMER-enhanced filter helps eliminate common household odors and true HEPA filtration captures and traps particles as small as 0.3 microns so you can breathe comfortably. Washable pre-filter helps capture larger particles and extends the life of HEPA filter. Filter life monitor alerts you when filter changes are needed to maintain maximum performance. Filters included. 3 speed settings to keep air fresh and pure; Filter monitors alert you when filter changes are needed; Recommended for rooms up to 310 square feet.